Effect of tetrachloronitrobenzene (fusarex) on emergence and yield of potatoes. Part III. — Northeast

Foundation seed potatoes of Katahdin, Kennebec and Pungo varieties were treated with Fusarex dust at three dates during the 1966–67 storage season. In 1967 these treated seed potatoes were planted in uniform tests and compared with untreated and desprouted seed potatoes. Cooperators in Maine, Long Island, New Jersey, Pennsylvania and Connecticut planted the seed lots, recorded plant emergence, and obtained yield data. Initial emergence of Fusarex-treated and desprouted seed was delayed when compared with untreated seed except in Pennsylvania where both initial and final emergence of Pungo and Kennebec was improved by Fusarex treatment. Final emergence of January and March Fusarextreated seed of all three varieties was better than that of untreated and desprouted seed in Pennsylvania. At all other locations improvement of plant stand by Fusarex seed treatment was very erratic. The March Fusarex treatments resulted in an average yield equal to the untreated seed. Yield of tubers from chemically treated Katahdin seed was not significantly affected when compared with untreated seed at four of the five locations. November treatment of Kennebec seed with Fusarex adversely affected yields at three of the five locations. In Connecticut all Fusarex seed treatments reduced yields of Kennebec. Pungo seed treated with Fusarex produced yields in most cases that were not statistically higher than that of untreated seed.